Process of making molds



- A. KUZNIK.

PROCESS OF MAKING MOLDS. APPLICATION man JULY n. 1919.

1,347, 1 68.- Patented July 20, 1920.

UNITED STATES PATENT OFFICE.

AUGUST KUZNIK, 0F CLEVELAND, OHIO, ASSIGNOR OF THREE-FOURTHS TO ANDREW LILLIE, OF CLEVELAND, OHIO.

IPROCESS' OF MAKING MOLDS.

Application filed July 11,

To all whom it may concern Be it known that I, AUcUs'r KUZNIK, a citizen of the United States, residing at Cleveland in the county of Cuyahoga and State of (5 and useful Improvement in Processes of Making Molds, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention relates to molds and has for its general object to insure the production'of castings which are free from sand and other impurities. I secure this general object in and through the manner of forming a mold shown in the drawings forming part hereof, wherein Figure 1 represents a central vertical sectional view through such mold; Fi 2 a sectional view corresponding to the line 22 of Fig. 1, the position of the pouring gateor opening in the cope being indicated in dot-and-dash lines; Fig. 3 a side elevation of a pattern employed in connection with the making of the mold and in the practice of my process; and Fig. 4 a detailin perspective of a core member employed in the making of such mold and the practice of such process. X y Describing the parts by reference characters, 1 denotes the drag and 2 the cope'of a mold of ordinary construction. In casting articles of various shapes, it is extremely desirable to keep the quality of the iron as high as possible and, with this object in view, I preferably provide in the mold a chamber for the reception of the molten metal-from which it is distributed to the mold cavity proper by means of a trapped outlet, thus insuring the presence at all times of a body of molten metal between the pour- .ing point and the mold cavity, whereby any sand or other impurities will be prevented from passing into the said cavity. In Fig. 1, I have shown a mold cavity at 3 communicating by a suitable channel 4 and a trapped outlet 5,-5 with the bottom ofan inter mediate chamber 6.

For the purpose of forming the intermediate chamber and the trapped outlet therefrom, I prefer to employ a pattern such as shown in Fig. 3. Thislpattern comprises an upper oval section 7 and a lower oval" section 8, the lower section being provided with a lateral projection 9 and a rounded.

rib 10 projecting from the middle of the rear of such projection and extending lon- Specification of Letters Patent.

hi0, have invented a certain new I Patented July 20, 1920. 1919. Serial 1109310448.

gitudinally of such projection as well as' therebeneath as shown at 11. In forming a mold by the use of the pattern 7-11, the pattern members will be supported in the mold box in the usual manner with the top of the section 8 and the top of the projection 9 and rib 10 at or near the top of the drag. The pattern will also be supported in the mold box in the usual manner. As shown herein, the top of the pattern has been supported substantially even withthe top of the drag, but this is merely for purpose of illustration. The sand then having been rammed, the cope is lifted from the drag, the patterns removed, and an opening 12 is provided, which preferably communicates with the upper portion of the chamber 6 which is formed by the removal of the patterns 711. A gate or filling opening 13 is also provided in the sand and is shown in the cope section, the bottom of said opening communicating with the central portion of the chamber 6 at one side and tangentially thereof, so that .a whirling motion will be imparted to the molten metal entering the same. There will then be formed in the sand a chamber 6 the bottom section of which is laterally enlarged and projecting toward the mold cavity 3, but spaced therefrom. A core 14 which is of the same shape as the lateral projection 9, with the excep tion that it is provided with a central vertical half round channel 15 and a bottom half' of core sand, the channel 4 is then formed in the sand in the top of the drag section and provides a continuous trapped outlet from the bottom of the chamber 6 to the top of the mold cavity 3.

In forming a mold the operator pours the molten metal into the gate or opening 13, and when this metal rises above the bottom of the channel 4, it may then enterthe mold cavity. By this mode of forming the mold, the mold chamber will be filled while maintaining at all times a body of molten metal in the chamber 6. .Any sand,

cinder, or other sediment which is of less gravity than the molten iron will evidently rise to the top of the iron in the chamber 6 and overflow from the outlet gate or opening 12. Because of the manner of introduction, the metal entering the chamber 6-iS given a whirling motion similar to that imparted by stirring with a ladle, and a certain proportion of the sediment will adhere to the sand constituting the wall thereof. By introducing the metal into the chamber (i below the top of the latter, the separation of the coke and sediment upwardly is fa cilitatedo .After the pouring operation, the metal in said chamber and in the trapped outlet may be removed and remelted. It will be noted that the chamber 6 is eggshaped and that the trapped outlet leads from the lowest point in the concave bottom thereof. lVith this shape of chamber, some whirling of the metal poured thereinto will occur, even though no special provision be made for introducing the metal tangentially of the chamber. Connecting the trapped outlet with the bottom of the chamber prevents the passage of any material amount of coke or other sediment into the molding cavity; for,,as soon as the horizontal lower portion of the trapped outlet is filled with the metal, the coke or other sediment is whirledoutwardly by centrifugal action and rises into the upper portion thereof, and, if present in large proportion, may even enter the outlet 12.

Having thus described my invention, what I claim is 1. A mold having, a molding cavity, a separating chamber provided with a concave bottom, a trapped outlet leading from the central portion of such bottom to the motion to such metal, and an outlet for sediment extending from the upper portion of said chamber.

3. A mold having a molding cavity, an egg-shaped separating chamber, a trapped outlet leading from the central portion of the bottom of said chamber to the molding cavity, an outlet for sediment extending from the top of said chamber, and a pouring gate communicating with said chamber.

4. A mold having a molding cavity, an egg-shaped separating chamber, a core forming part of the lower wall of said chamber and provided with a groove form-' ing part of a trapped outlet channel leading from the central portion of the bottom of said chamber to said cavity, an outlet for sediment extending from the upper portion of said chamber, and a pouring gate arranged to deliver molten metal tangentially of said chamber and between the top and the bottom thereof.

In testimony whereof I hereunto aflix my signature.

AUGUST KUZNIKt 

